1. Field of the Invention
The present invention relates to a charging process and a device thereof, and in particular to a charging device or a latent image forming device utilizing solid-state electron beam generating sources.
2. Related Background Art
Solid-state electron beam generating devices are already disclosed for example in the Japanese Patent Publication No. 30274/1979, Japanese Patent Laid-open Publication No. 111272/1979 (corresponding to the U.S. Pat. No. 4,259,678), Japanese Patent Laid-open Publication No. 15529/1981 (corresponding to the U.S. Pat. No. 4,303,930) and Japanese Patent Laid-open Publication No. 38528/1982.
Such charging, for example that commonly conducted in an electrophotographic process, is conducted usually with a corona charger, and, in the electrophotographic processes, the charging is generally conducted with such a process as to provide a uniform surface potential on a chargeable member such as a photosensitive member.
Also the U.S. Pat. No. 4,155,093 discloses a charging process of selectively charging the surface of a chargeable member, utilizing an electric discharge.
However such conventional charging processes utilizing a corona charge mentioned first are capable of forming a uniform surface potential on the chargeable member but are usable to form a desired charge pattern. Also the charging process mentioned next is unable, due to the characteristics of the charging device, to obtain different surface potentials simultaneously on different positions of the surface of the chargeable member.
Besides such charging devices have not been popularly employed due to various drawbacks such as the requirement of a high control voltage, the destruction of surface elements by sputtering, and a limit in the line density of the charge obtained.
Also in the field of electrostatic latent image forming devices utilizing an electron beam there are already known a so-called thin film penetration printing tube and electrostatic an charge printing tube. However the devices utilizing such tubes are inevitably large since such tubes require a relatively large vacuum space.
Furthermore, in such devices the end portions of the latent image are apt to be distorted, since these tubes rely on the deflection of a single electron beam.